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@article{DE_1967_3_12_a9, author = {A. B. Kurzhanskii}, title = {On the approximation of linear differential equations with lag}, journal = {Differencialʹnye uravneni\^a}, pages = {2094--2107}, publisher = {mathdoc}, volume = {3}, number = {12}, year = {1967}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1967_3_12_a9/} }
A. B. Kurzhanskii. On the approximation of linear differential equations with lag. Differencialʹnye uravneniâ, Tome 3 (1967) no. 12, pp. 2094-2107. http://geodesic.mathdoc.fr/item/DE_1967_3_12_a9/